850 gear reduction using Ranger parts

Anyone know where I can find some information on the swap, Ive heard it is possible to do, but cant find any info on it. Im interested in doing the swap for my 850 to get a little more grunt out of it. trying to not drop it as far as the highlifters are geared. I would like to use the 14 percent kit offered by other companies but they dont seem to have anything for newer than the 2011, which was able to be used if it had a shaft machined down.